Welding and weldability of ductile intermetallic alloys. [(Fe,Ni)/sub 3/(V,Ti); (Fe,Co)/sub 3/(V,Ti)]

Conference · Thu Jan 01 04:00:00 EST 1987

OSTI ID:6095247

David, S A; Santella, M L; Goodwin, G M

Successful welds have been produced in several nickel aluminide (Ni/sub 3/Al) alloys. Weldability has been found to be a strong function of boron, other alloying additions, and welding speed. Cracking during welding observed in some of the aluminides was predominantly in the heat-affected zone (HAZ) and was always intergranular. Additions of iron promote the formation of a second phase. The observed HAZ cracking in some of these alloys resulted from thermal stresses imposed on this region of the weldment at elevated temperature and from grain boundary weakness. Sound welds were produced in sheets of (Fe,Ni)/sub 3/(V,Ti) and (Fe,Co)/sub 3/(V,Ti) ordered alloys. Welds of (Fe,Ni)/sub 3/(V,Ti) were disordered, but the tensile properties were not adversely affected. A reordering heat treatment restored the weldment properties to those of the base metal. Welds of (Fe,Co)/sub 3/(V,Ti) remained ordered after the weld thermal cycle. Factors that seem to influence the weldment properties include ordered domain size and precipitation of carbide. 23 refs., 8 figs., 24 tabs.

• Research Organization: Oak Ridge National Lab., TN (USA)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6095247
• Report Number(s): CONF-870981-2; ON: DE87014061
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360101* -- Metals & Alloys-- Preparation & Fabrication
360102 -- Metals & Alloys-- Structure & Phase Studies
360103 -- Metals & Alloys-- Mechanical Properties
ALLOYS
ALUMINIUM ALLOYS
BORON ADDITIONS
BORON ALLOYS
COBALT ALLOYS
COBALT BASE ALLOYS
CRACKS
CRITICAL TEMPERATURE
CRYSTAL STRUCTURE
GRAIN BOUNDARIES
HARDNESS
HEAT AFFECTED ZONE
HEAT TREATMENTS
INTERMETALLIC COMPOUNDS
IRON ALLOYS
JOINTS
MECHANICAL PROPERTIES
MICROHARDNESS
MICROSTRUCTURE
NICKEL ALLOYS
NICKEL BASE ALLOYS
PHYSICAL PROPERTIES
STRESSES
TENSILE PROPERTIES
THERMAL STRESSES
THERMODYNAMIC PROPERTIES
TITANIUM ALLOYS
TRANSITION TEMPERATURE
VANADIUM ALLOYS
WELDABILITY
WELDED JOINTS
ZONES